Answer this question truthfully
### Question: What causes Papillary carcinoma of the thyroid?
### Response: The cause of this cancer is unknown. A genetic defect may be involved.
Radiation increases the risk of developing thyroid cancer. Exposure may occur from:
High-dose external radiation treatments to the neck, especially during childhood, used to treat childhood cancer or some benign childhood conditions. Radiation due to atomic bomb testing in the Marshall Islands and the 1986 Chernobyl nuclear disaster in the Ukraine, mostly in children.
Radiation given through a vein (through an IV) during medical tests and treatments does not increase the risk of developing thyroid cancer.